How Facebook will fight sex trafficking

Facebook’s software is a whiz at finding friends and picking out faces in photos. Now, the company will use its expertise to help find bad guys and rescue young victims of sex-trafficking operations.

On Thursday, New York Attorney General Eric Schneiderman announced Facebook (FB) engineers will help his office use “innovative data and analytical methods” to combat online child sex operations.

The plan involves the use of algorithms to scour internet ads, according to a press release describing the initiative. Specifically, the algorithms will look for patterns in images, text, phone numbers, and other data that turns up on sites where commercial sex is sold.

“Facebook is pleased to be working with Attorney General Schneiderman on his efforts to combat the scourge of human trafficking. We look forward to helping the Attorney General and his staff bring attention to this important issue,” said Facebook’s director of state public policy.

Facebook declined to further provide details, but a likely guess is the project will draw on Facebook’s massive database of “faceprints” to identify victims who appear in the sex ads. Faceprints serve as distinct digital identifiers, similar to a fingerprint, that are based on the unique contours of a person’s face. Facebook uses the technology to suggest tags for people when users post a photos.

In the case of sex-trafficking victims, law enforcement agencies could cross-check images of their faces to discover their identities—and possibly pictures of the people who are controlling them.

Update: Following the publication of this story, a Facebook spokesperson provided the following statement:

“Facebook is not providing the Attorney General’s office access to its facial recognition software or conducting any facial recognition on its platform as part of this agreement. Instead, Facebook will provide technical assistance to Schneiderman’s staff – at their request – in adopting existing, commercially available technology, that may help find trafficking victims online.”

In its release describing the initiative, the Attorney General’s office cited examples of pimps and sex trafficking rings who posted pictures of minors on websites like Backpage and Craigslist, describing the practice as “modern day slavery.”

The Attorney General’s office announced the Facebook partnership as part of a two-day summit on human trafficking that is taking place in Manhattan on Thursday and Friday. Facebook and Schneiderman have colloborated in the past, most recently on a project to send AMBER Alerts to the NewsFeeds of social network users when a child goes missing.

This story was updated at 12:35pm ET on Friday to add Facebook’s additional statement.

For more on Facebook’s facial recognition features and privacy, see this Fortune video.